Loft block with aligned sheaves

Patent metadata

Field	Value
Publication number	US-9962620-B2
Application number	US-201514968987-A
Country	US
Kind code	B2
Filing date	Dec 15, 2015
Priority date	Oct 27, 2011
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

A lift system configured to lift an article (e.g., a batten). The lift system includes a first cable configured to be coupled to the article, a second cable configured to be coupled to the article, a drive mechanism coupled to the first cable and the second cable and operable to raise and lower the article, a first loft block including a first loft sheave to redirect the first cable from a first substantially horizontal axis to a first substantially vertical axis, and a guide member to direct the second cable along a second substantially horizontal axis. The lift system further includes a second loft block including a second loft sheave to redirect the second cable from the second substantially horizontal axis block to a second substantially vertical axis.

First claim

The invention claimed is:

1. A lift system configured to lift an article relative to a structural member, the lift system comprising:
a first cable configured to be coupled to the article;
a second cable configured to be coupled to the article;
a drive mechanism coupled to the first cable and the second cable and operable to raise and lower the article;
a plurality of loft blocks including a first loft block positioned closer to the drive mechanism than the other plurality of loft blocks, the first loft block including a first loft sheave rotatable about a loft axis and configured to redirect the first cable from a first substantially horizontal axis to a first substantially vertical axis, the first substantially horizontal axis defined by a portion of the first cable positioned closer to the drive mechanism than the first loft block, the first loft block further including a guide member configured to support the second cable along a second substantially horizontal axis, the second substantially horizontal axis defined by a portion of the second cable positioned closer to the drive mechanism than the first loft block, and wherein the portion of the first cable is obliquely oriented relative to the portion of the second cable in a direction non-parallel to the loft axis; and
a second loft block of the plurality of loft blocks including a second loft sheave configured to redirect the second cable to a second substantially vertical axis,
wherein the guide member of the first loft block is located at least partially above the first substantially horizontal axis, and
wherein the first substantially vertical axis extends through the guide member such that at least a portion of the guide member vertically overlaps with the first loft sheave.

2. The lift system of claim 1 , wherein the first loft block includes a support adjacent a top end of the first loft block and configured to attach the first loft block to the structural member, wherein the guide member is located at least partially above the first horizontal axis such that at least a portion of the guide member is located between the first horizontal axis and the support in a direction along the first vertical axis.

3. The lift system of claim 1 , wherein the first loft sheave is mounted within a loft plane perpendicular to the loft axis, and wherein the guide member is mounted within the loft plane.

4. The lift system of claim 3 , wherein the guide member is centered on the loft plane.

5. The lift system of claim 3 , wherein the guide member is mounted for rotation in the loft plane.

6. The lift system of claim 5 , wherein the guide member is mounted for rotation about a guide member axis, and wherein the guide member axis is parallel to the loft axis.

7. The lift system of claim 1 , wherein the guide member includes an idler member.

8. The lift system of claim 1 , wherein the first and the second cables are wound and unwound around a common drum of the drive mechanism.

9. The lift system of claim 8 , wherein a traction drive is coupled between drum and the first loft block, wherein the traction drive is operable to guide the first and the second cables from the drum to the first loft block.

10. The lift system of claim 1 , further comprising a housing configured to be coupled to the structural member, the first loft sheave rotatably coupled to the housing about the loft axis, the guide member rotatably coupled to the housing about a guide member axis, wherein the guide member axis is positioned between the structural member and the loft axis.

11. A lift system configured to lift an article relative to a structural member, the lift system comprising:
a first cable configured to be coupled to the article;
a second cable configured to be coupled to the article;
a drive mechanism coupled to the first cable and the second cable and operable to raise and lower the article;
a plurality of loft blocks including a first loft block positioned closer to the drive mechanism than the other plurality of loft blocks, the first loft block including a first loft sheave configured to redirect the first cable from a first substantially horizontal axis to a first substantially vertical axis, the first substantially horizontal axis defined by a portion of the first cable positioned closer to the drive mechanism than the first loft block, the first loft block further including a guide member configured to support the second cable along a second substantially horizontal axis above the first substantially horizontal axis, the second substantially horizontal axis defined by a portion of the second cable positioned closer to the drive mechanism than the first loft block, wherein the portion of the first cable is spaced below the portion of the second cable; and
a second loft block of the plurality of loft blocks including a second loft sheave configured to redirect the second cable to a second substantially vertical axis,
wherein the guide member of the first loft block is located at least partially above the first substantially horizontal axis and the first substantially horizontal axis extends through the guide member.

12. The lift system of claim 11 , wherein the first loft block includes a support adjacent a top end of the first loft block and configured to attach the first loft block to the structural member, wherein the guide member is located at least partially above the first horizontal axis such that at least a portion of the guide member is located between the first horizontal axis and the support in a direction along the first vertical axis.

13. The lift system of claim 11 , wherein the first loft sheave is mounted for rotation about a loft axis and within a loft plane perpendicular to the loft axis, and wherein the guide member is mounted within the loft plane.

14. The lift system of claim 13 , wherein the guide member is centered on the loft plane.

15. The lift system of claim 13 , wherein the guide member is mounted for rotation in the loft plane.

16. The lift system of claim 15 , wherein the guide member is mounted for rotation about a guide member axis, and wherein the guide member axis is parallel to the loft axis.

17. The lift system of claim 11 , wherein the guide member includes an idler member.

18. The lift system of claim 11 , wherein the first and the second cables are wound and unwound around a common drum of the drive mechanism.

19. The lift system of claim 11 , wherein the first vertical axis extends through the guide member such that at least a portion of the guide member vertically overlaps with the first loft sheave.

20. A loft block assembly comprising:
a hanger configured to be secured to a structural member;
a loft sheave coupled to the hanger, the loft sheave configured to redirect a first cable from a first substantially horizontal axis to a substantially vertical axis; and
a guide member coupled to the hanger, the guide member configured to direct a second cable along a second substantially horizontal axis,
wherein the guide member is located at least partially above the first substantially horizontal axis so that the guide member is positioned and configured to inhibit contact between the guide member and the first cable, and wherein the substantially vertical axis extends through the guide member such that at least a portion of the guide member vertically overlaps the loft sheave.

Assignees

• Electronic Theatre Controls Inc

Inventors

• Hoffend Iii Donald A

Classifications

• B66C1/28

  Duplicate, e.g. pivoted, members engaging the loads from two sides · CPC title

• F16M13/022

  repositionable · CPC title

• B66D1/36

  Guiding, or otherwise ensuring winding in an orderly manner, of ropes, cables, or chains · CPC title

• B66C1/36

  with means, e.g. spring-biased detents, for preventing inadvertent disengagement of loads · CPC title

• B66D1/60

  adapted for special purposes · CPC title